Exhaust silencer



July 28, 1931. L. J. WOLFORD EXHAUST SILENCER Filed April 6, 1929 Attorney Patented July 28, 1931 PATENT OFFICE LESTER J. WOLFOBD, F LANSING, MICHIGAN EXHAUST SILENCE-R Application filed April 6,

This invention relates to a silencer, and more especially to an exhaust silencer for use on any kind of an internal combustion engine, and the primary object of the inveng, tion is to provide an exhaust silencer which will allow exhaust gases to escape without offering any resistance to the flow of gas, and yet at the same time mufile the sound of the explosion.

A still turther object of the invention is to provide a silencer of the type described which is comparatively simple'in structure, inexpensive, and comprises a casing having baflles disposed therein whereby the exhaust l gases will encounter no direct opposition,

and wherein the gases are directed through the silencer in a circular motion.

With the above and numerous other ob- -je'cts of the invention will become readily apparent during a study of the following description taken in connection with the accompanying drawings, wherein:

Figure l is a longitudinal. sectional view of the casing showing the manner of posi- 2 tioning the bafies therein.

Figure 2 is a transverse sectional view, and Fi re 3 is an end view of the silencer. With reference more in detail to the drawing it will be seen that my improved silencer embodies a casing designated generally at 5,

which casing comprises a plurality of sections, the sections being designated by the numerals 6, 7 and 8, respectively. While l have herein shown the casing as comprising but three sections, it is to be understood of course that the casing may have more or less sections as desired.

It is to be noted that the casing is substantially circular in cross section and that each of the sections oi the casing is relatively wide intermediate its ends and tapers towards its ends. By so forming the sections rela-v tively small inlets 9 and outlets 10 are formed at the opposite ends of the respective sections.

45 As illustrated, the casing is preferably formed of one piece, and it is to be noted that the sections graduate in size beginning at the inlet 11 of the casing, the last section, counting from the left to the right in Figure 1., being the largest. Within each of the sections 6, 7,

1929. Serial- No. 353,130.

the full length of the bafle between the hams I and the wall of the section. Each of the said fins are twisted in a manner best shown in Figure 2. lit desired, the bafie may be anchored within its section by means of a bolt 14 passing through the center of the bafile, and the opposite ends of the bolt 14 projecting outwardly from opposite sides of the section. Nuts l515 are threadly mounted on the respective ends of the bolt 14 for rigidly securing the bolt in place in the section. lit is to be noted that each of the respective sections of the casing are practically identical in shape, except that the last of the sections is provided with a flared mouth 16 to insure there being no obstruction in the path of the discharge gases. It is also to be noted that the bathe 13 in each of the sections is of substantially the same shape differentiating in size only. Each of the baiiles 13 is of a size corresponding to the size of the respective sections.

The fins of the bullies may be disposed at any angle within the sections and have their longitudinal edges disposed in contact with the walls of the sections, and the fins running parallel with the gas flow to provide a greater sound absorbing surface.

Thus it will be seen that l have provided a casing so shaped as to allow battles of a stream line or aerodynamic shape or both to be contained therein, and it is further obvious that the first battle, that is. the battle disposed in section 6 of the casing which the gas will encounter gives to the gas outward motion toward the wall of the casing where it is cooled by the casing, since the casing is cooled by the outside air. The fins on the bafies, due to their peculiar shape as shown will also serve 'to give the gas a circular motion which enables the gas to flow more easily and in a natural manner. This cirtion to the other so that by the time the gases have been exhausted through the flared opening they have so increased in velocity as to completely eliminate all back pressure upon the motor. In providing the casing with the flared openin 16 the outside air is thrown away from t e gas flow and thus eliminates the pressure due to exhaust gases coming directly in contact with the air. The action of the air being thrown outwardly by the flared mouth leaves a slight vacuum within the casing which the gas must relieve and so consequently causing the gases to leave the last section more quickly which in turn draws the gas from the sections more rapidly. Another advantage of so forming my casing is thatthe outside air will come in contact at the point of greatest diameter, thus cooling the casing and in turn cooling the gases inside which will then contract, thus decreasing in volume and leavin more space for the oncoming gas thus tending to eliminate back pressure.

.l claim as new and desire to From the foregoing, it will be apparent that the bafiles 13 extend longitudinally of the casing andin the line of flow of the exhaust gases entering the casing and flowing therethrough in the direction indicated by the arrow in Figure l, the bafies thus afiording' little or no obstruction to the flow of gases through the casing progressively from one section to the other.

one end thereof and tapering towards its opposite end, a bafle arranged 1n each of said sections and being of a shape corresponding approximately to the shape of its section, said baflles respectively provided with diametrically opposed fins contacting at their free edges with the walls of the respective sections, said fins extending longitudinally of the respective bafiles, each of said fins being twisted, each of said bafiles being of a length less than the length of its section, and bolts extending diametrically through the baflies and having their respective ends extending through the walls of the respective sections, and nuts threaded on the ends of the bolts. In testimony whereof I afiix mysignature.

LESTER J. WOLFORD.

While I have herein shown the preferred embodiment of my invention it is to be understood that certain changes in details, and the construction thereof may be resorted to without departing from the spirit of the invention as herein described and claimed.

Having thus described the invention, what secure by Letters Patent is Q 1. An exhaust silencer comprising a plurality of integral sections progressively increasing in length and meandiameter from one end to the other of the silencer, each of said sections being relatively wide adjacent one end thereof and tapering towards its opposite end, a bafiie arrangedin each of said sections and being of a shape corresponding approximately to the shape of its section, said bafiies respectively provided with diametrically opposed fins contacting at their free edges with the walls of the casing, said fins extending longitudinally of the respective bafiles, and each of said fins being twisted.

2. An exhaust silencer comprising a plurality of integral sections progressively increasing in length and mean diameter from one end to the other of the silencer, each of said sections being relatively wide adjacent 

